1. Field of the Invention
The present invention relates to a method for modifying a metal surface which is performed by irradiating energized ion particles onto the surface of a metal under a vacuum condition.
2. Description of the Prior Art
When the surface of a polymer is modified by using an ion beam, an action between the polymers and the energized ion beam causes polymeric chains comprising the polymer to be cleaved by the ion beam and the cleaved chains are combined with one another, which is referred to as a crosslink phenomenon. When an ion beam or hundreds of KeV with a high energy is incident to a polymer, most couplings of chains are cleaved, which is referred to as a carbonization. When the ion beam is irradiated, if a reactive gas is simultaneously introduced such as oxygen or nitrogen on the surface where unstable chains the couplings of which are cleaved exist, a new polymer is formed due to a chemical reaction between the cleaved unstable chains and the reactive gases.
When an energized ion particle is irradiated onto the surface of an oxide to modify the surface characteristic, oxygen included in the oxide existing on the surface is eliminated and the element of an atmospheric gas is combined instead, as an attempt to increase a desired bond or an strength.
As to kinds of bondings in a material to be modified, a covalent bond is formed in the case of a polymer, and a mixed type of a covalent bond and an ionic bond in the case of an oxide. In the case of a polymer or an oxide, a new covalent bond or an ionic bond is formed on the surface thereby to form a desired bonding and change the property of the surface.
When comparing the surface modification of the polymer or oxide, it can be seen that the surface property can be modified by forming a new ionic bond or a covalent bond on the surface of the material composed by a metal bonding by free electron. The generation of the new ionic bond or the covalent bond formed on the surface of the metal can increase Van der Waals bonding with another material. Therefore, a strong adhesion to another material can be achieved and a hydrophilic property can be enhanced.